Aquatic Hemiptera. 
8i 
placed it on a heap of perfectly dry plaster of Paris powder and entirely covered it 
with the same. After it had remained in the plaster for about a couple hours the in- 
sect was thoroughly dusted with a rather stiff sable hair brush. This treatment pre- 
vents the hairs on the body and legs from lying flat when specimens are taken out of 
alcohol and pinned. 
Apart from the pinned specimen becoming slightly darker than the one in alco- 
hol, the two do not differ from one another. 
The colour of the hairs on the apices of the femora, on the tibiae and on the 
tarsi of the intermediate and posterior legs is not 
entirely yellow as it is in the species mentioned by 
Distant in the Fauna, but it varies according to the 
colour of the part of the legs to which they are 
attached, that is those on the yellowish parts are 
yellowish and those on the darker parts are blackish. 
There are two parallel rows of hairs on the tibiae 
of the intermediate and posterior legs. 
The hairs on the outer parts of the anal appendages 
are also dark. 
In the alcohol specimen there are three very small, 5-—Cercotmetus compositus. 
.1. Head and thorax, x 2. 
conspicuous, black tubercles on the outer margm of 2. Hind leg. x2. 
the connexivum, placed almost above the middle of 
the 2nd, 3rd and 4th abdominal segments respectively. In the dried specimen these 
tubercles are very indistinct. 
The points on which I have relied for the identification of these specimens are:— 
the pronotum is wider posteriorly than anteriorly ; the interocular tubercle is obtuse 
or blunt, not pointed ; the membrane is well-developed, passing the apical angle of the 
corium and covering about half the apical abdominal segment; the intermediate fem- 
ora are longer than the head and pronotum together; the mesosternum is plain, the 
metasternal carina not reaching it. 
Family NAUCORIDAE. 
Naucoris sordidus, Dist. 
1910. Naucoris sordidus, Distant, W. L-, Fauna of British India, Rhynchota, V (Appendix), 
p. 325, text-fig. 186. 
One specimen from a small pool or ditch at the edge of the lake. Tale Sap, Pata- 
lung, i3-i-i6. 
This specimen agrees very closely with Distant 's description of A^. sordidus, but 
his figure does not agree with specimens he has identified, especially with regard to 
the markings on the connexivum, which in the specimens are identically the same as 
those in the figure of N. vividus (p. 326). I have no hesitation in identifying the 
Siamese specimen as N. sordidus as the markings on the pronotum resemble those in 
the figure of sordidus rather than those in that of vividus. 
